Rotary pump



Nov. 18, 1930. A BARGEBQER 1,782,282

ROTARY PUMP FledrMay 14, 1929 Patented Nov. 18, 1930 l, UNITED STATESPATENT oFFlcF.

. ADOLF BABGROER, F THEn BAGUE, NETHERLANDS ROTARY PUMP Application ledIcy 14, 1929, Serial No. 862,989, and in Great Britain April 4, 1989.

My present invention, Lwhich relates to a rotary pump or compressor,more especially to a self-sucking rotary pump for liquids, gases ormixtures of these fluids, hasv for its I principal object a pump of thistype which, while simple and reliable in construction, is exceptionallyefcient in operation. With this object in view, I suggest to provide theannular,crescentshaped or otherwise formed l'channel between thecircumferential portion of the'blade wheel or impeller and the innerwall of the pumping space with inwardly xtending shoots or branchesforming recesses in one or in both side walls of 4said space.

In order that my invention may be clearly understood'by one skilledinthe art, I shall describe some embodiments thereof with reference tothe annexed drawing, on which Fig. 1 is a vertical, axial sectionalIelevan tion of a rotary pump,

Fig; 2 is an end elevational inner view of -said pump and p Figs. 3-5are innerA elevational views of modified sidewalls of the pumpingspace.v

In accordance ing of the pump is composed of a casting 1 provided with asuction nozzle 3, and of a casting 2 having a liquid chamber 4 and a,discharge nozzle 5.. The shaft 6, which is supported by -a bearing 7and sealed by a stuiiing box 8 both located in the casting 2, carries atits one end, intermediate between both castings 1 and 2, a blade wheelor im peller 9 secured thereto by meansfof a nut 10.

The pumping space has a cylindrical circumferential wall 11 which iseccentric` with respect to the shaft 6 and the impeller 9, so that acrescent-shaped channel 12 is left between the circumference of theimpeller and the said cylindrical wall 11. -Said channel 12 has aplurality of shoots 13 forming recesses in both side walls of the'pumping space, i. e. in the vfacing walls of vcastings 1 and 2, saidshoots being inwardly and spirally bent in the direction of. rotation ofthe impeller and closeds at their inner ends.

Withinthe channel 12, the casting 1 is provided with an inlet openingv14 and the casting 2 both with an outlet opening 15 and a 5 back flowopening 16.

with Figs. 1 and 2, the cas-9 In the embodimentslshown in Figs. 3-5, theimpeller `is assumed to be coaxial with and snugly fitting within thecylindrical pumping space, the channel 12 b'einglocated on one or,preferably, on either side of the impeller. AIn tangential direction,said channel 12 only extends segmentally from the inlet open/ingv 14 ltothe outlet opening 15. In accordance with Fig. 3,-one shoot 13 of the`channel '12 is located'intermediate between the end portion of saidchannel and the out-V p let opening 15; Fig. 4 shows an embodiment inwhich the last shoot partly registers with the.outlet opening 15 and inwhich, moreover, the backflow opening 16 has been dispensed with. Thisis also the ,case in the embodiment illustrated in Fig. 5, in which thechannel 12 is subdivided by bridges 17 into a plurality of segmentalsections and in which the end sections are in communication with oneanother through a relatively narrow passage 18.

The described pump functions as follows: Assuming the pump to becompletely filled with water and the shaft to be rotating at Ahighspeed, then lthegimpeller will throw the water in an approximatelytangential direction into the channel'12. In normal operation, the wateri'n said channel flows in substantially7 the samejdirection but at amuch lower speed.1 Owing to the excess of speed of the inflowing water,both the speed and .the pressure of the water in the channel 12 peller.Obviously, each shoot 13 will deviate part of the water in van inwarddirection, whereby the water is returned intoy the impeller and againaccellerated, so that' it is again thrown withy full circumferentialspeed onto the water iowing through channel 12. Thereby, andA also owingto the presence of local strictures that may be provided axially orradially in the channel 12, preferably just beyond the opening of eachshoot 13 see Fig. 4), the pressure rapidly increases in the direction ofrotation of the impeller, so that the water is forcibly driven to thepressure side of the pum Initially, when the pump begins to suck, boththe chamber 4 and the pumping space are y increase `in the direction ofmotion of the im completely filled with water. If, now, the impeller isd riven at high speed, it forces the water within the pumping space inoutward direction. This causes a certain vacuum to set up, but as thepressure increases in the direction of rotation, said vacuum gradually,

decreases..l andafteip-a certain -tirnesan overpressure is set up, sothat the a'ir is discharged thru the outlet opening. The spiral line 19in Fig. 2 approximately indicates the inner circumference of the Vmassof water within the pumping space in this stage of the operation.

As the vacuum in the suction pipeof the pump increases, thepump..requires an increased quantity of water, owing, inter alia,

- to the reduction of the amount/of water within the pumping space. Thiscondition is met by water from chamber 4 flowing back` into thepumpingspace, either through the out?. let opening 15 (Figs. 4 and 5).,or through one or more special return flowv openings 16 (Figs. 1-3)until the water in the suction pipe enters into and fcompletely fillsthe pumping space.

The same'purpose 1s served by the narrow channel 18 (Fig. 5) connectingthe pressure and the suction ends of the channel 12 fand through which acertain quantity of water from the pressure end of the channel 12 isdelivered to the suction end of this channel,

depending from the difference of pressure atv both lends.

Y vIt will be understood that the described pump can aswell be used asan air pump or as acompressor. If the pump does not require to draw inair or other gas, the outlet 15 may open into the circumferentialchannel 12.

The shoots 13 may be more or less, or even exactly radial and may have avariable cross sectional area.

It is preferred to provide the rotary impeller with,fiat, radial blades.A rearward curvature. would tend to reduce theA outlet velocity of thewater, whereas a forward curvature would materially increase theinternal resistance of the pump.

I wish it to be well understood that the expression pump in thisspecification and in the claims appended thereto is to be sobroadlyconstrued as to also cover-a compressor.

WhatIclaimis:

1. In a rotary pump, a casing enclosing a pumping space having two sidewalls, an 1mpeller'adapted for rotationwithin said space 'andttingbetween said sidewalls, a channel space and fitting between saidside walls, a

channel formed between the circumferential portion of said impeller andthe walls of` said space, an inlet opening in one of said side walls andlocated within said channel, an outlet opening in the other side wall,and a plurality of shoots of said channel extending A inwardly andforming recessesina side wall Of Said space. 4

3. In a rotary pump, a casing enclosing a pumping space having two sidewalls, an impeller adapted for rotation within said s ace and fittingbetween said side walls, a vc annel formed between the circumferentialportion of said impeller and thewalls of said space, an inlet opening inone of said-side,

l walls and located within said channel, an outlet opening in the otherside wall, and ashoot of said channel extending inwardly and forml ingrecesses in both of said side walls. V 4. In' a rotary pump, a casingenclosing a pumping space having two sidewalls, an 1mpeller adapted forrotation within said spacev and fitting between said side walls, achannel formed between the circumferential portion of said impeller andthe Walls of said space, an inlet openin lin one of said side walls andlocated wit in said channel, an outlet opening in the other side wall,and a .plurality of shoots of seid channel each extendees ing inwardlyand forming recesses' in bgthf said side walls. s; 5. In a rotary pump,a casin enclosing apumping space 'aving two si e walls, an impelleradapted for rotationwithin said space and fittingl'between said sidewalls, a channel formed etween the circumferential portion ofsaidimpeller and the .walls of said space and havlng a variable crosssectional area, an inlet openin in one of said side walls and locatedwithln said channel, an outlet opening in the other side wall, and ashoot of said channel extending inwardly and forming a recess 'in a sidewall of said space.

6. In a rotary pump, a casing enclosing a pumpingspace havingtwo sidewalls, an 1mller adapted for. rotation within said space and fittingbetweensaid side walls, a crescentshaped 'channel formed between thecircumferential vportion of said impeller and the walls of said space,an inlet opening in oneof said side walls and located within saidchannel, an outlet o eningin the 4other side wall, and a shoot ,o saidchannel extending inwardly and forming a recessin a side wall of sadsace. 7. n a rotary Rump, .a casin -enclosing a pumping space aving twosi e walls, an impeller adapted for rotation 4within .said space andfittin between said side walls, a channel formedetween thecircumferential portion of vsaid impeller space, an inlet openin in one.ofsaid side walls and located wit 'n said channel, 'an

and the walls of said.

outlet o ening in the other side wall, and a shoot ci) said channelextending inwardly 'and forming a recess in a side wall of said space,the said channel being reduced in cross sectional area forward of theaxis of said shoot reckoned in the direction ofrotation of saidimpeller.

8. In a rotary pump, a casing enclosing a pumping space having two sidewalls, an 1mpeller adapted for rotation within said space and fittingbetween said side walls, a channel formed between the circumferentialportion of said impeller and the walls of said space, an inlet openin inone of said side walls and located wit in said channel, an outletopening in the other side wall and registering with part of the saidchannel, and a shoot of said channel extending inwardly and forming arecess in a side Wall of said space.

9. In-a rotary pump, a casing enclosing a pumping space having two sidewalls, an impeller adapted-for rotation within said space and fittingbetween said side walls, a channel formed between the circumferentmlportion `of said impeller and the walls of said space, an inlet openingin one of said 'side walls and located within said channel an outletopening in the other side wall, an a shoot of saidchannel extendinginwardly and forming a recess in a-s1de wall, said shootregisteringwithsaid outlet opening. 10. In a rotary. pump, a casing enclosing -apumping space having two side walls, an

e impeller adapted for rotation within said CTI space and iittinbetweenl said side walls, a channel formed etween the circumferentialportion of saidimpeller and the walls of said'space, an inlet opening inone of said side walls and located within said channel, an outletopening in the'other side wall, a shoot of said channel extendinginwardly and :forming a recess in a side wall of said space, and areturnliow opening in the side wall which is provided with the saidoutlet opening. y

11. In a rotary pump, a casin enclosing a pumping space having two si ewalls, an impeller adapted for rotation within said space and fittingbetween said side walls, a sectional channel formed between thecircumferential portion of said impeller and the walls of said space, aninlet ope in one of said side walls and located said channel, an outletopenin in the other side wall, and a shoot of sai channel extendinginwardly and forming a recess in' a side wall of said space.

12. In a rotary pump, a casing enclosing a pumping space having two sidewalls; an impeller adapted `for rotation within said space and fittingbetween said side walls, a segmental channel formed between thecircumferential portion of said im eller and the walls of said space theen of said channel being in communication with one 7( formmg a recess 1na slde wall of said space.

In testimony whereof I aiix m si nature.

i ADOLF BARG B ER.

